Chinese state banks have substantial dollar deposits (it is largely state banks that are lending to companies like Evergrande offshore). The PBOC stopped issuing notes (and sterilising the dollar inflow) years ago, and onshore dollar deposits are above $1tn. A lot of the stuff you read about this online is exceptionally misleading (I have no idea why there is this cottage industry of "economic experts" who don't understand economics...it is parallel to the gold bug industry, it is very weird).